Apparatus for testing pneumatic tools.



N'b."'839, 1l1. PATENTED DEC. 25, 1906.

' y R. A. CHAMBERS;

APPARATUS FORTESTING PNEUMATIC TOOLS.

APPLICATION I'I I IED JULY 23, 1908.

Witnesses 120mm. aumz VWZ I THE NORRIS PETERS co., WASHINGTON, o. c.

1 w ll whom it may cancer-'11 j UNITED STATES PATENT, OFFIC ROBERTALLisoN- CHAMBERS, OF NEW GLASGOW, NOVA scorIA, CANADA.

APPARATUS FOR TESTING PNEUMATIC TOOLS.

-Be it known that '1, ROBERT 'ALLrsoN CHAMBERS, of the town of NewGlasgow, Province of Nova Scotia, and Dominion of Canada, haveinventedcertain new and useful-Improvements in Ap aratus for TestingPneumatic Tools, of W 'chthefollowing is a full,

clear, and exact description.

My invention relates to apparatus for testing pneumatic tools andsimilar devices;

and its object is to provide a means for subjecting the tools toresistances and stresses which are the equivalents of those met with inactual operation. To accomplish this object,I provide a frame supportinga testingcylinder and provided'with means for securing the'tool to betested. Connected to the cylinder are an open reservoir containing waterand two closed tanks containing air. Adjacent the pneumatictool. is achamber provided with pressure and temperature recording'me'ans. Gagesare provided for registering the'pressure of air supplied to the tooland also the pressure of air in the two closed tanks. Check-valves areplaced between the cylinder and the reservoir and be-.

tween thecylinder and each ofthe tanks. Adjustable gates' are'furtherprovided for the cylinder, whereby its functions may be regulate'd tosuit the class of tool to be tested.

'Referring to the drawings which illustrate my invention, Figure 1 is aside elevationof the device, showing the relative positionof the parts;Fi 2' is a vertical longitudinal section throng Fig. 3 'is a verticallongitudinal section through the center of the exhaust-muffler. Fig; 4is a cross-sectional view of the cylinder on the line XX ofFig. 2. 4

In the above-defined figures,

1 designates the frame of'the machine, one" end of which carriesanexhaust-muflier 2 and a pair of adjustable clamps 3 and; the other end aclosed cylindrical tank 4 and an open reservoir 5,

supported on a plurality of columns 6. Toward the center the frame 1carries a cylinder 7, open atthe end 8. The cylinder 7 is provided withadjustable gates 9 and 9 which open or close the ports 10 and 10 in thecylinder. Inside the cylinder 7 is a piston 11, which when operated bythe pistonrod 12 retreats and allows water from the tank 5 to enter thecylinder through the pipe 13 and check-valve 14. On the forward strokeof the piston the water is allowed to escape through the port 10 on theside of Specification of Letters Patent.

Application filed July 23, 1906. Serial No. 327.294.

the center of the cylinder.

I Patented Dec. 25; 1906'- the cylinder until the piston passes thisport. When the piston has passed the port 10*, the resistance to itsforward motion, due tothe water column, will cause an impact whichforces the waterthrough the pipe 15 past the check-valve 16 and into thetank 4, compressing the air therein, which pressure is registered by thegage 17. These repeated impacts correspond to the blows when inoperation. The vacuum causedin the tank maintained by the check-valve 18and registered by the gage 35. The end of the piston-rod 12 is hollow at19 and provided with a set-screw 20 for securing the end of a cutter orother member 21, actuated by the pneumatic tool 22, which is firmly setup in the clamps 3 by means, of adjusting-screws 23. The supply-pipe 24of the. tools 22 is provided with a pressure-gage 25, andthe-exhaust-pipe 26 discharges into the muffler 2,. The muffler 2contains a plurality of angularly-disposed bafiie-plates 27, which causethe exhaust to be equally distributed throughout the muflier 2 before itescapes through the orifice 28. Athermometer 29 and a water or mercurycolumn 30 are inserted into and pressure of the exhaust. A pipe 31,provided with a valve 32, leads'from the bottom of the tank 4 into thereservoir 5, so that when the test is finished the valve 32 may beopened and the pressure of air in the tank 4 utilized to return thewater to the reservoir 5. As a further auxiliary I provide an airclosedtank 34, attached tothe pipe 15 be+ yond the check-valve 18, said tankprovided with a vacuum-gage 35. The return stroke of the piston createsa partial vacuum "in the tank 34, which vacuum corresponds to theresistance to the return motion of the toolcutter 21 experienced inactual operation.

The operation of my device consists, briefly, in registering thepressure of air supum created in the tanks 4 and 34, and also thepressure, volume, and temperature of theair after it has passed throughthe tool.

The pneumatic tool 22, which is rigidly fixed by the clamps 3, operatesthe piston 11 through the medium of its cutter 21, which is fixed tothepiston-rod 12 by a set-screw 20. The commencement of the forwardstroke of the piston 12 creates a partial vacuum in the tank 34, whichvacuum is maintained by the 34 by the return stroke of the piston 11 isthe muffler'2 to ascertain'the temperature cook 33 in the tank 4. I alsoprovide a plied to the tool, the air-pressure and vacucheck-valve 18 andcorresponds approximately to the resistance met with on the returnstroke of the cutter 21 in actual practice. The length of thevacuum-stroke may be regulated by the gate 9 to accord with theconditions under which the tool would normally operate. During theremainder of the forward stroke the cylinder fills with water from thereservoir 5. At the commencement of the return stroke the check-valvecloses and the water in the cylinder is forced out through the port 10until the piston passes this port. The sudden resistance to the forwardmovement of the piston caused by the imprisoning of the water in thecylinder 7 isthe equivalent of the impact of the cutter in actualoperation. The continuous repetition of these resistances or impactscompresses the air in the tank 4 through the medium of the water in thecylinder, a small portion of which is forced past the checkvalve 16 andinto the tank 4 at each forward stroke of the piston. The air-pressurethus caused is registered by the gage 17 and represents the momentum orefficiency of the tool. The length of stroke during which the water isforced into the tank 4 may be regulated by means of the gate 9*. Theexhaust from the tool 22 is led into a chamber 2, containing a pluralityof bafHelates 27, which diffuse the jet of exhaust flui rendering itsdensity uni form, so that its temperature and pressure H may beaccurately registered by the gages 29 and 30 before it escapes throughthe orifice 28. When the test is completed, the water in the tank 4 maybe returned to the reservoir 5 by opening the valve 32 and allowing theair-pressure in the tank to force the water through the pipe31.

The advantages of this device are that a pneumatic tool may be subjectedto all resistances and stressesexperienced in actual operation and suchres stances accurately measured and compared with the amount of owerrequired to overcome them, thereby furnishing a reliable means forgaging the power and efficiency of the tool and for setting the Valvesof the same. 4

Having thus described my invention so that the same may be readilyunderstood by those skilled in the art to which it appertains, what Iclaim, and desire to secure by Letters Patent, is

1. In a device of the class described, a cylinder, a piston therefor,adjustable means for introducing a column of water into said cylinder, acompressor-tank, means connecting said compressor-tank and cylinder, areciprocating tool attached to said piston, and means for registeringthe impact of the piston against a column of water Within the cylinder.

2. In a device of the class described, a cylinder, a piston therefor, anadjustable inletport on one side of said cylinder, an adjustableoutlet-port on the opposite side of said cylinder, a compressor-tank,means connecting said compressor-tank and cylinder, a reciprocating toolconnected to said piston, and means for registering the impact of theforward stroke of the piston.

3, In a device of the class described, a cylinder, a piston therefor, anadjustable inletport at one side of said cylinder, an adjustableoutlet-port 011 the opposite side of said cylinder, a compressor-tank,means connecting said compressor-tank and cylinder, a reciprocating toolconnected to said piston, means for measuring the impact of the forwardstroke of the piston, and means for measuring the return stroke of thepiston.

4. In a device of the class described, a cylinder, a piston therefor,adjustable means for introducing a column of water into said cylinder,an adjustable outlet-port, a compressor-tank, means connecting saidcompressor-tank and cylinder, a vacuum-tank, means connecting saidvacuum and cylinder, a reciprocating tool connected to said piston,means for measuring the impact of tie forward stroke of said plston,means for measuring the return stroke of the piston, and means formeasuring the energy required by said. reciprocating tool.

5. A device of the class described comprisin ,a cylinder, a pistontherefor, an adjustab e inlet-port on one side of said cylinder, anadjustable outlet-port on the opposite side of the cylinder, acompressor-tank, a vacuumtank, connections between said tanks andcylinder, areciprocating tool connected to said iston, means formeasuring the energy supp ied to said tool, and means for measuring theforward and return strokes of said piston.

In witness whereof I have hereunto set my hand in the presence of twowitnesses.

ROBERT ALLISON CHAMBERS.

Witnesses:

STUART R. W. ALLEN, C. W. TAYLOR.

